#region License

/*
 * Copyright © 2002-2011 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#endregion

using System.Reflection;

namespace Spring.Objects.Factory.Config {

	/// <summary>
	/// Subinterface of
	/// <see cref="Spring.Objects.Factory.Config.IObjectPostProcessor"/>
	/// that adds a before-instantiation callback and a callback after instantiation but before
	/// explicit properties are set or autowiring occurs.
	/// </summary>
	/// <remarks>
	/// <para>
	/// Typically used to suppress default instantiation for specific target objects,
	/// for example to create proxies with special <c>Spring.Aop.ITargetSource</c>s (pooling targets,
	/// lazily initializing targets, etc), or to implement additional injection strategies such as field
	/// injection.
	/// </para>
	/// <para>
	/// This interface is a special purpose interface, mainly for internal use within the framework.
	/// It is recommended to implement the plain <see cref="IObjectPostProcessor"/> interface as far as
	/// possible, or to derive from <see cref="IInstantiationAwareObjectPostProcessor"/> in order to be shielded
	/// from extension to this interface.
	/// </para>
	/// </remarks>
	/// <author>Juergen Hoeller</author>
	/// <author>Rick Evans (.NET)</author>
	public interface IInstantiationAwareObjectPostProcessor : IObjectPostProcessor
	{
		/// <summary>
		/// Apply this
		/// <see cref="Spring.Objects.Factory.Config.IObjectPostProcessor"/>
		/// <i>before the target object gets instantiated</i>.
		/// </summary>
		/// <remarks>
		/// <p>
		/// The returned object may be a proxy to use instead of the target
		/// object, effectively suppressing the default instantiation of the
		/// target object.
		/// </p>
		/// <p>
		/// If the object is returned by this method is not
		/// <see langword="null"/>, the object creation process will be
		/// short-circuited. The returned object will not be processed any
		/// further; in particular, no further
		/// <see cref="Spring.Objects.Factory.Config.IObjectPostProcessor"/>
		/// callbacks will be applied to it. This mechanism is mainly intended
		/// for exposing a proxy instead of an actual target object.
		/// </p>
		/// <p>
		/// This callback will only be applied to object definitions with an
		/// object class. In particular, it will <b>not</b> be applied to
		/// objects with a "factory-method" (i.e. objects that are to be
		/// instantiated via a layer of indirection anyway).
		/// </p>
		/// </remarks>
		/// <param name="objectType">
		/// The <see cref="System.Type"/> of the target object that is to be
		/// instantiated.
		/// </param>
		/// <param name="objectName">
		/// The name of the target object.
		/// </param>
		/// <returns>
		/// The object to expose instead of a default instance of the target
		/// object.
		/// </returns>
		/// <exception cref="Spring.Objects.ObjectsException">
		/// In the case of any errors.
		/// </exception>
		/// <seealso cref="Spring.Objects.Factory.Support.AbstractObjectDefinition.HasObjectType"/>
		/// <seealso cref="Spring.Objects.Factory.Support.IConfigurableObjectDefinition.FactoryMethodName"/>
		object PostProcessBeforeInstantiation(Type objectType, string objectName);


        /// <summary>
        /// Perform operations after the object has been instantiated, via a constructor or factory method,
        /// but before Spring property population (from explicit properties or autowiring) occurs.
        /// </summary>
        /// <param name="objectInstance">The object instance created, but whose properties have not yet been set</param>
        /// <param name="objectName">Name of the object.</param>
        /// <returns>true if properties should be set on the object; false if property population
        /// should be skipped.  Normal implementations should return true.  Returning false will also
        /// prevent any subsequent InstantiationAwareObjectPostProcessor instances from being
        /// invoked on this object instance.</returns>
        bool PostProcessAfterInstantiation(object objectInstance, string objectName);

	    /// <summary>
	    /// Post-process the given property values before the factory applies them
	    /// to the given object.
	    /// </summary>
	    /// <remarks>Allows for checking whether all dependencies have been
	    /// satisfied, for example based on a "Required" annotation on bean property setters.
	    /// <para>Also allows for replacing the property values to apply, typically through
	    /// creating a new MutablePropertyValues instance based on the original PropertyValues,
	    /// adding or removing specific values.
	    /// </para>
	    /// </remarks>
	    /// <param name="pvs">The property values that the factory is about to apply (never <code>null</code>).</param>
	    /// <param name="pis">he relevant property infos for the target object (with ignored
	    /// dependency types - which the factory handles specifically - already filtered out)</param>
	    /// <param name="objectInstance">The object instance created, but whose properties have not yet
	    /// been set.</param>
	    /// <param name="objectName">Name of the object.</param>
	    /// <returns>The actual property values to apply to the given object (can be the
	    /// passed-in PropertyValues instances0 or null to skip property population.</returns>
	    IPropertyValues PostProcessPropertyValues(IPropertyValues pvs, IList<PropertyInfo> pis, object objectInstance, string objectName);
	}
}
